/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the  "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id$
 */
package wx.xml.xalan.xalan.templates;

import javax.xml.transform.TransformerException;

import wx.xml.xalan.xalan.res.XSLTErrorResources;
import wx.xml.xalan.xalan.transformer.TransformerImpl;
import wx.xml.xalan.xml.utils.XML11Char;
import wx.xml.xalan.xpath.XPathContext;

/**
 * Implement xsl:processing-instruction.
 * <pre>
 * <!ELEMENT xsl:processing-instruction %char-template;>
 * <!ATTLIST xsl:processing-instruction
 *   name %avt; #REQUIRED
 *   %space-att;
 * >
 * </pre>
 *
 * @xsl.usage advanced
 * @see <a href="http://www.w3.org/TR/xslt#section-Creating-Processing-Instructions">section-Creating-Processing-Instructions in XSLT Specification</a>
 */
public class ElemPI extends ElemTemplateElement {
    static final long serialVersionUID = 5621976448020889825L;

    /**
     * The xsl:processing-instruction element has a required name
     * attribute that specifies the name of the processing instruction node.
     * The value of the name attribute is interpreted as an
     * attribute value template.
     *
     * @serial
     */
    private AVT m_name_atv = null;

    /**
     * Get the "name" attribute.
     * DJD
     *
     * @return The value of the "name" attribute
     */
    public AVT getName() {
        return m_name_atv;
    }

    /**
     * Set the "name" attribute.
     * DJD
     *
     * @param v Value for the name attribute
     */
    public void setName(AVT v) {
        m_name_atv = v;
    }

    /**
     * This function is called after everything else has been
     * recomposed, and allows the template to set remaining
     * values that may be based on some other property that
     * depends on recomposition.
     */
    public void compose(StylesheetRoot sroot) throws TransformerException {
        super.compose(sroot);
        java.util.Vector vnames = sroot.getComposeState().getVariableNames();
        if (null != m_name_atv)
            m_name_atv.fixupVariables(vnames, sroot.getComposeState().getGlobalsSize());
    }


    /**
     * Get an int constant identifying the type of element.
     *
     * @return The token ID for the element
     * @see wx.xml.xalan.xalan.templates.Constants
     */
    public int getXSLToken() {
        return Constants.ELEMNAME_PI;
    }

    /**
     * Return the node name.
     *
     * @return The element's name
     */
    public String getNodeName() {
        return Constants.ELEMNAME_PI_STRING;
    }

    /**
     * Create a processing instruction in the result tree.
     * The content of the xsl:processing-instruction element is a
     * template for the string-value of the processing instruction node.
     *
     * @param transformer non-null reference to the the current transform-time state.
     * @throws TransformerException
     * @see <a href="http://www.w3.org/TR/xslt#section-Creating-Processing-Instructions">section-Creating-Processing-Instructions in XSLT Specification</a>
     */
    public void execute(
        TransformerImpl transformer)
        throws TransformerException {

        if (transformer.getDebug())
            transformer.getTraceManager().fireTraceEvent(this);

        XPathContext xctxt      = transformer.getXPathContext();
        int          sourceNode = xctxt.getCurrentNode();

        String piName = m_name_atv == null ? null : m_name_atv.evaluate(xctxt, sourceNode, this);

        // Ignore processing instruction if name is null
        if (piName == null)
            return;

        if (piName.equalsIgnoreCase("xml")) {
            transformer.getMsgMgr().warn(
                this, XSLTErrorResources.WG_PROCESSINGINSTRUCTION_NAME_CANT_BE_XML,
                new Object[]{Constants.ATTRNAME_NAME, piName});
            return;
        }

        // Only check if an avt was used (ie. this wasn't checked at compose time.)
        // Ignore processing instruction, if invalid
        else if ((!m_name_atv.isSimple()) && (!XML11Char.isXML11ValidNCName(piName))) {
            transformer.getMsgMgr().warn(
                this, XSLTErrorResources.WG_PROCESSINGINSTRUCTION_NOTVALID_NCNAME,
                new Object[]{Constants.ATTRNAME_NAME, piName});
            return;
        }

        // Note the content model is:
        // <!ENTITY % instructions "
        // %char-instructions;
        // | xsl:processing-instruction
        // | xsl:comment
        // | xsl:element
        // | xsl:attribute
        // ">
        String data = transformer.transformToString(this);

        try {
            transformer.getResultTreeHandler().processingInstruction(piName, data);
        } catch (org.xml.sax.SAXException se) {
            throw new TransformerException(se);
        }

        if (transformer.getDebug())
            transformer.getTraceManager().fireTraceEndEvent(this);
    }

    /**
     * Add a child to the child list.
     *
     * @param newChild Child to add to child list
     * @return The child just added to the child list
     * @throws DOMException
     */
    public ElemTemplateElement appendChild(ElemTemplateElement newChild) {

        int type = ((ElemTemplateElement) newChild).getXSLToken();

        switch (type) {

            // char-instructions
            case Constants.ELEMNAME_TEXTLITERALRESULT:
            case Constants.ELEMNAME_APPLY_TEMPLATES:
            case Constants.ELEMNAME_APPLY_IMPORTS:
            case Constants.ELEMNAME_CALLTEMPLATE:
            case Constants.ELEMNAME_FOREACH:
            case Constants.ELEMNAME_VALUEOF:
            case Constants.ELEMNAME_COPY_OF:
            case Constants.ELEMNAME_NUMBER:
            case Constants.ELEMNAME_CHOOSE:
            case Constants.ELEMNAME_IF:
            case Constants.ELEMNAME_TEXT:
            case Constants.ELEMNAME_COPY:
            case Constants.ELEMNAME_VARIABLE:
            case Constants.ELEMNAME_MESSAGE:

                // instructions
                // case Constants.ELEMNAME_PI:
                // case Constants.ELEMNAME_COMMENT:
                // case Constants.ELEMNAME_ELEMENT:
                // case Constants.ELEMNAME_ATTRIBUTE:
                break;
            default:
                error(XSLTErrorResources.ER_CANNOT_ADD,
                    new Object[]{newChild.getNodeName(),
                        this.getNodeName()});  //"Can not add " +((ElemTemplateElement)newChild).m_elemName +

                //" to " + this.m_elemName);
        }

        return super.appendChild(newChild);
    }
}
